Special thanks to Dieter Scherk for providing this lens for testing purposes!

Introduction

The Zeiss Vario-Sonnar T* 24-70mm f/2.8 ZA SSM is a hint of the things to come.
It is a full format standard zoom lens that is more or less openly targeting
Sony's upcoming professional-grade 24mp FF DSLR but it does naturally work
perfectly on the existing lineup of APS-C DSLRs where its field-of-view is equivalent
to about 36-105mm in classic terms.

Regarding its weight of nearly 1kg the Zeiss 24-70mm f/2.8 ZA feels like a
massive block of glass. However, this is not overly unusual - the Canon
and Nikon counterparts are in the same weight- and size-league. Upon closer inspection
you may be a bit surprised that the lens is not an all-metal construction.
The inner tube as well as the lens hood are made of metal indeed but Sony
used plastics for parts of the outer body. Plastics may sound bad but it is a high-quality
variant ... although it does still not feel really right regarding the positioning
of the lens. Unfortunately the lens does not feature any seals which is also
a bit of a faux-pas.
The zoom ring operates a bit stiff - surely a side-effect of the heavy
weight of the glass. The handling of the focus ring is smoother. Typical
for most Sony lenses both control rings have an inevitable tendency to collect
dust in no time "thanks" to the fluted rubber design.

Looking at the product
shots below you may notice that the lens extends when zooming from 24mm towards
the long end of the range. The Zeiss uses an internal focusing design so the
front element does not rotate during focusing (nor zooming) operations.

One of the interesting features of the lens is the SSM - the SuperSonic AF Motor which is similar to Canon's USM or Nikon's SWM. The SSM is not
really a new thing for Sony/Minolta users - Minolta released the first SSM lenses
several years ago - but so far Sony was quite shy to take advantage of it for whatever
reason. The SSM of the Zeiss is ultra-fast, near silent and very accurate. More of this
please! Sony/Zeiss did also incorporate a focus-lock button plus a dedicated AF/MF
switch.